1. Field of the Invention
The present invention relates to an apparatus and a method for reproducing an optical recording medium, and more particularly, to an apparatus and method for determining an area of an optical disc, in which inner and outer regions of an optical disc with an absolute time of 99 minutes may be differentiated from each other by referring to a number of an absolute time-code in pre-groove (ATIP) syncs.
2. Description of the Related Art
In general, as shown in FIG. 1, an optical disc having an absolute time of 90 minutes consists of three signal areas: a lead-in area; a program area; and a lead-out area. The lead-in area contains information recorded on the optical disc, such as location information, the type of disc, and reproduction time. In the lead-in area, which is called a table of content (TOC) area, a TOC signal is repeatedly recorded. A reproduction signal is recorded in the program area, and the ending of a program is indicated in the lead-out area. Referring to FIG. 1, except for an optical disc having the absolute time of 99 minutes, a 90-99 minute area is present only in the lead-in area (shown as 95-99 minutes in the example in FIG. 1). For access to an optical disc, time information of a pickup is converted into a logical block address (LBA) to measure a distance of movement of the pickup. In this case, current time information of the pickup is converted into −LBA when the pickup is present in the lead-in area and converted into +LBA when the pickup is present in the area other than the lead-in area, i.e., the program area or the lead-out area.
FIG. 2 is a flowchart illustrating a conventional method of determining the area of an optical disc. Referring to FIG. 2, whether current time information of a pickup is 95 minutes or more is checked using ATIP information which is recorded on an optical disc, in operation 200. If the current time information of the pickup is 95 minutes or more, the pickup is regarded as being currently positioned in a lead-in area, and current time information of the pickup is converted into −LBA, in operation 201. However, if the current time information of the pickup is less than 95 minutes, the pickup is judged to be currently located in an area other than the lead-in area, and the position of the pickup is converted into +LBA, in operation 202.
However, in the case of an optical disc having an absolute time of 99 minutes, 90-99 minute areas are present in both a lead-in area and the area other than the lead-in area, i.e., a program area or a lead-out area, as shown in FIG. 3. Therefore, whether a pickup is present in the lead-in area or an area other than the lead-in area must be determined. Otherwise, when the pickup is present in a 95-99 minute area, a seek error may occur. The area of the optical disc where a pickup is located has to be determined to measure a distance of movement of the pickup precisely. Then, the position of the pickup is converted into −LBA when the pickup is judged to be present in the lead-in area and converted into +LBA when the pickup is judged to be present in an area other than the lead-in area. Accordingly, the distance of movement of the pickup may be precisely measured, thus rendering precise access to a desired point of the optical disc.